Every day, every hour, a bustling life goes on behind the scenes at ­Princeton. Many of the 13,700 people who live or work at the University hardly notice these essential ­operations unless something goes wrong. This unseen Princeton often is a world of strenuous work, fast paces, and very early rising.

PHOTO: RICARDO BARROS
PHOTO: RICARDO BARROS

Some say this is the future of libraries — gargantuan, shared regional warehouses like this one on Forrestal Campus, home to nearly 10 million items from Prince­ton and other prestigious institutions. No browsing allowed: Forklifts shuttle up and down ReCAP’s 34 aisles (soon to increase to 58), where books are packed ­closely together by size, not subject matter, and shelving soars to 30 feet. The 11 workers wear jackets and hats, as they work in rooms maintained at 55 degrees Fahren­heit, optimal for paper. Some books never see Firestone at all: Publishers send them directly to ReCAP, from where they can be retrieved when requested. The name stands for: Research Collections and Preserva­tion Consortium.

Luis Mendoza, cook, Dining Services
Luis Mendoza, cook, Dining Services
PHOTO: RICARDO BARROS

The era of the soggy French fry is over: Campus dining has been transformed in recent years, and now offers a multitude of dishes prepared in gleaming, renovated facilities. Dining Services is a sprawling operation, with more than 500 employees — 200 of them students — working in 19 facilities. Tigers are a hungry bunch, annually devouring almost a quarter-million pounds of poultry, 7,665 gallons of ice cream, and more than 5 million individual Cheerios. Space is the biggest challenge. Kitchens like the one at the Graduate College, shown top left, ­originally were designed for much smaller, less varied operations.

Heather Minnich, pastry chef/manager, Dining Services
Heather Minnich, pastry chef/manager, Dining Services
PHOTO: RICARDO BARROS

Out of sight in the basement of Madison Hall, the bakery gets going before 4 every morning, sending delicious smells wafting through the air by dawn. Here are produced nearly all the sweets eaten on campus plus dough balls for pizza — up to 1,000 balls per week for every residential ­dining hall. Volumes are immense, with a staff of just seven baking 70 dozen cookies at a time and using more than 3,000 pounds of butter a year.

PHOTO: RICARDO BARROS

Deep inside Jadwin Hall, Mike Souza blows glass instruments for scientists here and nationwide. It’s “hair-pulling” work, he says — especially making vessels with walls as thin as a human hair but capable of holding pressurized gas. (Imperfect tubes might burst, meaning costly interruptions for researchers.) Once Prince­ton had five glass blowers, but Souza, in the trade 40 years, is the only one remaining: Hyper­sensitive modern instrumentation has reduced the need for bulky glass ­vessels in labs. In his 2,000-degree flame, anything can go wrong. “Take alumino­silicate glass,” he says. “It cools really quick, like Super Glue. But if I heat it too quickly, it explodes.”

PHOTO: RICARDO BARROS

In Princeton’s tree nursery across Lake Carnegie, established nearly a century ago, an offspring of the ­18th-century Mercer Oak awaits replanting at Palmer House. As venerable specimens die among the main campus’s 6,000 trees, nursery plants replace them. Fewer universities have nurseries nowadays in spite of their many advantages: Trees thrive better on campus if they have grown in local soils, carefully tended by staff who avoid excessive fertilizer or damaging the roots. Because long-popular red oaks, hemlock, and ash increasingly suffer from diseases, the nursery recently has become home to other choices, including columnar oaks and flowering apricot.

PHOTO: RICARDO BARROS

Large academic buildings need thousands of sprinkler heads, tested and repaired at a fabrication shop on Alexander Street. Two hundred sprinkler systems on campus are maintained by six workers, up from just one man a generation ago (since a fatal fire at Seton Hall University in 2000, New Jersey has required sprinklers in every dorm room). Should a freshman use a sprinkler head as a towel-hook, breaking the glass bulb inside, 20 gallons a minute cascade as a signal alerts Public Safety within a minute. Actual dorm fires are rare: just two small ones in recent years, both doused by sprinklers.

Troy Lee, mail carrier, University Services
Troy Lee, mail carrier, University Services
PHOTO: RICARDO BARROS

Eighteen employees work at high speed in Mail Services’ two campus locations. The volume of regular mail has dropped lately, to 1.35 million pieces annually, but package deliveries to students are up 40 percent in four years, to 104,000. Some students receive hundreds of packages, their contents as varied as schoolbooks, ­bottled water, futons, and ­55-inch TVs. Because one-quarter of the undergraduate population leaves every year, undeliverable mail is copious; staff spend more than two hours a day trying to forward mail to Tigers who graduated up to six years previously. Three tons of undeliverable bulk mail was recycled last summer alone.

PHOTO: RICARDO BARROS

When winter storms strike, 75 workers spring into action, clearing snow from enough roads and paths to stretch to Atlantic City, plus 3,000 steps. Recent years have brought changes: avoidance of grass-killing salts, pretreatment of surfaces with a brine mixture made here. Plastic-composite blades on snowplows are replacing metal ones that scratch bluestone pavers, and rotary brooms offer gentler abrasion. “Expectations are different now,” says Al Pearson, who has plowed campus snow since 1979. “In years past, parts of campus were not cleared until the next day.” Today, they don’t wait.

PHOTO: RICARDO BARROS
PHOTO: RICARDO BARROS

Energy-hungry Princeton saves money and cuts its ­carbon output by using cogeneration: Hot exhaust from electricity generation makes steam to warm campus build­ings. Energy-plant manager Ted Borer and 23 staff members keep the ­facility going constantly, buying electricity off the regional grid when it’s cheap but making their own when the price rises, hour by hour. Some­times they chill a 2.6 million-gallon tank of water, then use it for air-conditioning instead of buying expensive power. “What makes the plant unique,” Borer says, “is how we control it and use it to the University’s best ­advantage.”